I also did not have a "Select all" box but was able to check the first entry, scroll down, hold shift, and check the last box which then selected all items in between. So I removed all of 600 of my accounts in about 20 seconds. Hope this helps someone.
Shift+Click to select a range is so second nature by now I don’t think it would have occurred to me to look for (or on the flip side, create) a dedicated “all” button.
Just me of course but I don't think I'd guess that without certain UI cues. With checkboxes for eg I wouldn't even think of shift clicking. Not disagreeing, just thinking aloud :)
For me it’s second nature in desktop applications and file management, but I never assume that the any specific web dev has added it. (And tbh: I have less and less confidence in web code in general.)
Shouldn't be a second nature, that is a good old well known useful pattern like right click for context menu, very essential.
Even if new methods are coined by some local reasons old and generic ones should be remembered to avoid the hopeless chaos the UX partisans push us into nowadays, doing things differently for the sole sake of doing differently.
